✨ Math Magic: Algebraic Symbols! ✨
Welcome to our super fun math note! By studying this lesson, you will be able to identify known terms, unknown terms, and variables. Let's dive in!
🔢 Section 1: Symbols Used in Maths
Math is like a secret language, and it uses special symbols to tell stories!
- The symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 are defined as digits.
- All the numbers are written using these ten digits.
Mathematical Operations
We also have symbols for actions, called mathematical operations:
| Mathematical Operation |
Symbol |
| Addition |
+ |
| Subtraction |
− |
| Multiplication |
× |
| Division |
÷ |
🌟 Example: The statement that thirteen is obtained by adding five to eight can be expressed using symbols as 8 + 5 = 13.
🕵️ Section 2: Known and Unknown Terms
What is a Known Term?
Sometimes, we know the exact number in our math story.
- We know that there are seven days in a week.
- The symbol 7 is used to express this constant number which we know.
- These constant values are called known terms.
What is an Unknown Term?
Sometimes, a constant value is hidden from us!
- Suppose a household buys the same amount of milk each day, but we do not know the amount.
- Such constant values which are not known are defined as unknowns.
- An unknown term is most often represented by a simple letter of the English alphabet, like a.
👧🏽 🫒 👦🏻
🌟 Example - The Olive Mystery:
Look at Nimal and Sita holding olives in their hands.
- The number of olives in Sita's hand can be written using the numerical symbol "3", which is a known number.
- We cannot say definitely how many olives there are in Nimal's hand.
- This unknown constant value (unknown term) can be represented by the letter b.
🥥 Section 3: Variables (The Shapeshifters!)
Some numbers are not constant at all—they change!
- Think about buying coconuts at the market.
- There are coconuts of various prices to be sold.
- Because the selling price of a coconut does not take a fixed value, we say the price is a variable.
- Variables are denoted using English letters like x, y, z.
🌟 Variable Examples:
- The daily revenue of a certain shop is Rs x.
- The distance a vehicle travels during an hour is y km.
📝 Section 4: Sample Questions and Answers
Question 1: Is "The number of days in the month of February" a constant value or a variable?
Answer: It is a variable (because it can be 28 or 29 days depending on leap years).
Question 2: Is "The number of centimeters in a metre" a constant value or a variable?
Answer: It is a constant value (it is always exactly 100).
Question 3: If a household purchases two litres of milk each day, how do you express the amount purchased in a week using symbols?
Answer: 2 × 7 = 14.
🎯 Section 5: Interactive Master Quiz!
Let's test what you've learned! Answer the 10 questions below, then click submit to see how you did.